Oil well derrick substructure with carriages for blowout preventers

ABSTRACT

The framework of an oil well derrick substructure has a slot extending from one side inwardly past the well center line, with track means secured to the framework and extending along at least one side of the slot from its inner end to its outer end and then laterally along the adjoining side of the framework. Supported by the track means is a carriage that extends outwardly for supporting a blowout preventer stack. The carriage can be moved along the track means back and forth between a position at the inner end of the slot to a position outside of the slot beside the outside of the framework, whereby a blowout preventer stack can be moved from outside the framework to a position over the well and vice versa.

United States Patent 1191 Donnally 1 1 Feb. 27, 1973 OIL WELL DERRICK SUBSTRUCTURE WITH CARRIAGES FOR BLOWOUT PREVENTERS Robert B. Donnally, Tulsa, Okla.

Lee C. Moore Corporation, Tulsa, Okla.

Filed: April 15, 1971 Appl. No.: 134,128

Inventor:

Assignee:

References Cited UNITED STATES PATENTS 3/1970 McEwen et al ..166/79 7/1966 l-lainer ..105/29 R 3,023,808 3/1962 St. John ..166/79 Primary Examiner-Robert G. Sheridan Attorney-Brown, Murray, Flick & Peckham [57] ABSTRACT The framework of an oil well derrick substructure has a slot extending from one side inwardly past the well center line, with track means secured to the framework and extending along at least one side of the slot from its inner end to its outer end and then laterally along the adjoining side of the framework. Supported by the track means is a carriage that extends outwardly for supporting a blowout preventer stack. The carriage can be moved along the track means back and forth between a position at the inner end of the slot to a position outside of the slot beside the outside of the framework, whereby a blowout preventer stack can be moved from outside the framework to a position over the well and vice versa.

7 Claims, 5 Drawing Figures OIL WELL DERRICK SUBSTRUCTURE WITII CARRIAGES FOR BLOWOUT PREVENTERS In the drilling of oil wells, blowout preventer equipment or stacks are used which are mounted on the upper ends of the well casings. The stacks are rated for working pressures over a large range, and also are made for connection to casings of different sizes. During a drilling operation different blowout preventers may have to be used at different stages of the drilling. The handling of the stacks to move them into and out of operating position is always a problem.

It is among the objects of this invention to provide apparatus by which blowout preventers of different sizes or capacities can be quickly and easily moved into and out of operative position, and which provides for ready storage of the stack that is not in use.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which FIG. 1 is a side view of an oil well drilling substructure;

FIG. 2 is a plan view taken on the line IIII of FIG.

FIG. 3 is an enlarged fragmentary plan view of a carriage;

FIG. 4 is an enlarged fragmentary side view of the carriage; and

FIG. 5 is a vertical section taken on the line VV of FIG. 4.

Referring to the drawings, the structural steel framework 1 of an oil well derrick substructure has a working floor 2 elevated a considerable distance above the ground or above the deck of a drilling barge. The framework and floor are provided with a wide slot 3 that extends from one side of the substructure inwardly past the center line of the well. The opposite sides of the slot at its outer end curve outwardly away from each other and merge into the flat side of the substructure. Track means are secured to the framework and extend along at least one side, and preferably both sides, of the slot from or near its inner end out to its outer end and then laterally along the side of the substructure at opposite sides of the slot. The track means include rails 4 mounted on the substructure framework, and upper and lower track members below the rails and parallel to them. The upper track member 5 preferably is an I-beam or a T-beam secured to a side surface of the framework directly below the rail, with the web of the beam horizontal and extending outwardly away from the framework. Each lower track member 6 may be a similar beam or it may be a long bar or channel secured to the framework several feet below the upper track member.

Supported by the track means at each side of slot 3 is a carriage that extends outwardly therefrom. Each carriage has a rectangular body formed from upper and lower pairs of horizontal channels secured together and connected by vertical channels 8. This body is spaced outwardly from the framework of the substructure and its upper pair of channels 9 support two pairs of short parallel horizontal bars 10 that extend toward the framework. The inner ends of the upper bars of these pairs slide on the rail and thereby support the carriage. In other words, the carriage is hung from the rail. To prevent the carriage from moving away from the rail, upper and lower horizontal wheels I] are pivotally connected to the bars on vertical axes and engage the inner surfaces of the vertical flange along the outer edge of the web of beam 5, as shown in FIG. 5. To keep the bottom of the carriage from swinging in toward the substructure, horizontal wheels 12 are journalled in the lower pair of channels 13 of the carriage body and roll against the outer surface of the lower track member 6.

Connected to the opposite ends of the carriage body are arms 15 that extend outwardly away from it.

Preferably, the inner ends of the arms are pivotally connected to the upper channels by vertical pivot pins 16, and inclined braces 17 secured to the outer ends of the arms are connected to vertical pivot pins 18 extending through lugs 19 at the ends of the lower pair of channels as shown in FIG. 4. These arms are for supporting the lugs that project from the opposite sides of a blowout preventer stack, with the stack 20 between the arms as indicated in dotted lines in FIGS. 1 and 2. The arms can be locked in their inner or parallel position by removable pins 21 extending through the upper channels 9 and lateral projections 22 on the inner ends of the arms.

In order to move the carriages along the tracks, a reversible motor 24 is mounted in the central area of each carriage and drives a pinion 25 on the upper end of its vertical shaft. The pinion meshes with a long gear rack 26 that extends along the side of the substructure slot and out along the outer side of the substructure framework. The rack is parallel to the rail and track members and is rigidly supported by brackets 27 secured to the framework. By operating the motor, the carriage can be made to travel from one end of the track to the other.

By having two carriages, each on its own track, one of them can carry a blowout preventer stack into the substructure slot into position over the well and stay there until it is necessary to change stacks, or the empty carriage can be returned to the outside of the substructure. When the stack is in position, the usual travelling block is connected to it and it is raised slightly so that the carriage arms 15 can be swung away from each other after their locking pins 21 have been removed. Then the blowout preventer is lowered between the arms onto the upper end of the casing and connected to it. When necessary to change stacks, the stack in the slot is carried out by the carriage and another stack, supported by the other carriage, is carried into the slot and connected up.

According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described We claim:

1. An oil well derrick substructure comprising a structural steel framework provided with a slot extending from one side inwardly past the well centerline, track means secured to the framework and extending along a side of said slot substantially from its inner end out to its outer end and then laterally along said side of the framework at one side of the slot, the portion of the track means along said side of the framework extending at an angle to the portion of the track means between the inner and outer ends-of said slot, a carriage supported by said track means and extending outwardly therefrom as a cantilever for supporting a blowout preventer stack beside the track means, and means for moving the carriage along the track means back and forth between a position at the inner end of the slot to a position outside of the slot beside said side of the framework, whereby a blowout preventer stack can be moved from outside the framework to a position over the well and vice versa.

2. An oil well derrick substructure according to claim 1, in which said track means include a rail supporting the upper part of the carriage, and means holding the top of the carriage against movement away from the framework.

3. An oil well derrick substructure according to claim 1, in which said track means include a rail supporting the upper part of the carriage, and upper and lower track members extending parallel to the rail, the upper member having an outer flange with a surface facing said framework and the lower member having a surface facing away from the framework, the carriage including laterally spaced upper horizontal wheels engaging said flange surface at longitudinally spaced points thereon, and a lower horizontal wheel engaging said surface of said lower member, said carriage moving means including a rack bar secured to said framework parallel to said track means, a pinion journalled in the carriage midway between said wheels and meshing with the rack bar, anda motor carried by the carriage for driving said pinion.

4. An oil well derrick substructure according to claim 1, in which said track means include a rail, an upper beam parallel to the rail and having an upright flange spaced outwardly from the framework, and a lower track member parallel to the rail, the carriage including means seated on said rail and movable along it for supporting the carriage, upper laterally spaced horizontal wheels engaging the inner surface of said beam flange, and a lower horizontal wheel engaging the outer surface of said lower track member.

5. An oil well derrick substructure according to claim 1, including second track means secured to the framework at the opposite side of said slot and extending laterally away from the outer end of the slot along said side of the framework, a carriage similar to the first-mentioned carriage supported by the second track means, and means for moving the second carriage along the second track means for moving a blowout preventer stack into the slot when the other carriage is outside of the slot.

6. An oil well derrick substructure according to claim 1, in which said carriage includes a body, a pair of laterally spaced arms extending outwardly therefrom in the same general direction for supporting a blowout preventer stack, and means pivotally connecting the inner ends of the arms to said body on vertical axes, whereby the outer ends of the arms can be swung laterally away from each other.

7 An oil well derrick substructure according to claim 1, in which said track means include a rail supported by the top of said framework, and means between the framework and the top of the carriage holding the carriage against movement away from the framework, the carriage being provided with means extending over said holding means and resting on said rail for supporting the carriage. 

1. An oil well derrick substructure comprising a structural steel framework provided with a slot extending from one side inwardly past the well centerline, track means secured to the framework and extending along a side of said slot substantially from its inner end out to its outer end and then laterally along said side of the framework at one side of the slot, the portion of the track means along said side of the framework extending at an angle to the portion of the track means between the inner and outer ends of said slot, a carriage supported by said track means and extending outwardly therefrom as a cantilever for supporting a blowout preventer stack beside the track means, and means for moving the carriaGe along the track means back and forth between a position at the inner end of the slot to a position outside of the slot beside said side of the framework, whereby a blowout preventer stack can be moved from outside the framework to a position over the well and vice versa.
 2. An oil well derrick substructure according to claim 1, in which said track means include a rail supporting the upper part of the carriage, and means holding the top of the carriage against movement away from the framework.
 3. An oil well derrick substructure according to claim 1, in which said track means include a rail supporting the upper part of the carriage, and upper and lower track members extending parallel to the rail, the upper member having an outer flange with a surface facing said framework and the lower member having a surface facing away from the framework, the carriage including laterally spaced upper horizontal wheels engaging said flange surface at longitudinally spaced points thereon, and a lower horizontal wheel engaging said surface of said lower member, said carriage moving means including a rack bar secured to said framework parallel to said track means, a pinion journalled in the carriage midway between said wheels and meshing with the rack bar, and a motor carried by the carriage for driving said pinion.
 4. An oil well derrick substructure according to claim 1, in which said track means include a rail, an upper beam parallel to the rail and having an upright flange spaced outwardly from the framework, and a lower track member parallel to the rail, the carriage including means seated on said rail and movable along it for supporting the carriage, upper laterally spaced horizontal wheels engaging the inner surface of said beam flange, and a lower horizontal wheel engaging the outer surface of said lower track member.
 5. An oil well derrick substructure according to claim 1, including second track means secured to the framework at the opposite side of said slot and extending laterally away from the outer end of the slot along said side of the framework, a carriage similar to the first-mentioned carriage supported by the second track means, and means for moving the second carriage along the second track means for moving a blowout preventer stack into the slot when the other carriage is outside of the slot.
 6. An oil well derrick substructure according to claim 1, in which said carriage includes a body, a pair of laterally spaced arms extending outwardly therefrom in the same general direction for supporting a blowout preventer stack, and means pivotally connecting the inner ends of the arms to said body on vertical axes, whereby the outer ends of the arms can be swung laterally away from each other. 7 An oil well derrick substructure according to claim 1, in which said track means include a rail supported by the top of said framework, and means between the framework and the top of the carriage holding the carriage against movement away from the framework, the carriage being provided with means extending over said holding means and resting on said rail for supporting the carriage. 